As is discussed in U.S. Pat. Nos. 3,791,076, 3,830,033 and 3,930,344, attention has been given to providing the metal frames of greenhouses with fastening means for securing plastic sheets to the frames to provide holding power all along the length of the plastic sheets. An excellent structure for such a purpose is disclosed in the aforementioned patents.
A similar problem arises in gutter connected greenhouses and is compounded as these structures may extend up to 500 feet in length with a large number of rafter members from adjacent greenhouses supported, via connections, to either side of an intermediate gutter which in turn is supported upon internal common columns. It is the primary object of the present invention to provide fastening means for securing plastic cover sheets to a bearing gutter which interconnects adjacent greenhouses.
The present invention provides an effective fastener for the plastic sheets along the edges of the gutters and in so doing, provides a fastening device which can also be utilized along the side and lower portions of a greenhouse structure if so desired.
The invention then provides, along each of the upper edges of the connecting gutter between two greenhouses, male and female members extending the length of the roof structure and having mating V-shaped sections provided with similarly longitudally extending splines on opposing surfaces, between which the ends of the plastic roof sheets are clamped, the female member providing a longitudally extending outer flange facing the splined sections of the male and female member and generally parallel therewith. The flange provides at spaced intervals along its length, internally threaded screw holes for the reception of thumb screws which can be "bottomed out" when tightened against the male member; that is, the screws are threaded at a ninety degree angle to the flange of the female member and to the inter-fitting splines of the male and female members.
It can be appreciated that the male and female members of the gutter can be provided at the terminal side of the greenhouse which is not gutter connected to another greenhouse and can provide means for securing the terminal end of side-wall sheets to the greenhouse.